1,720,967 research outputs found
Molecular Point-of-Care diagnostic for Treponema pallidum subsp. pertenue (yaws)
No full textThe eradication of yaws a neglected tropical disease caused by Treponema pallidum subsp. pertenue, which affects children living in very deprived hard to reach rural communities is constrained by the lack of rapid, accurate diagnosis. I sought to develop a molecular point-of-care test for the diagnosis of yaws. A Loop-mediated isothermal amplification (LAMP) assay with primers targeting the conserved gene, tp0967, with visual detection by lateral flow test strip was developed and optimized. The limit of detection was evaluated while 63 samples from clinical cases of yaws and 5 samples with PCR-confirmed syphilis were used to determine the sensitivity and specificity of the assay compared to the current molecular testing protocol. Reagents were dried in tubes and tested up to 14 days. The developed LAMP assay was found to be optimal when run at 65oC in a water bath for 30 minutes. The limit of detection was 2.7*104 DNA copies/ml. The sensitivity of the LAMP assay using unextracted and DNA extracted samples were 0.67 and 1.00 respectively. None of the syphilis samples tested positive in any of the assays. We show the development of a fast and sensitive LAMP assay for yaws detected by lateral flow test strip. Using extracted DNA, the assay sensitivity is at par with gold standard detection. The assay can be adapted to minimal sample processing required for in-field detection without DNA extraction.</div
Design and Fabrication of Soft Biosensors and Actuators
No full textSoft materials have gained increasing prominence in science and technology over the last few decades. This shift from traditional rigid materials to soft, compliant materials have led to the emergence of a new class of devices which can interact with humans safely, as well as reduce the disparity in mechanical compliance at the interface of soft human tissue and rigid devices.One of the largest application of soft materials has been in the field of flexible electronics, especially in wearable sensors. While wearable sensors for physical attributes such as strain, temperature, etc. have been popular, they lack applications and significance from a healthcare perspective. Point-of-care (POC) devices, on the other hand, provide exceptional healthcare value, bringing useful diagnostic tests to the bedside of the patient. POC devices, however, have been developed for only a limited number of health attributes. In this dissertation I propose and demonstrate wireless, wearable POC devices to measure and communicate the level of various analytes in and the properties of multiple biofluids: blood, urine, wound exudate, and sweat.Along with sensors, another prominent area of soft materials application has been in actuators and robots which mimic biological systems not only in their action but also in their soft structure and actuation mechanisms. In this dissertation I develop design strategies to improve upon current soft robots by programming the storage of elastic strain energy. This strategy enables us to fabricate soft actuators capable of programmable and low energy consuming, yet high speed motion. Collectively, this dissertation demonstrates the use of soft compliant materials as the foundation for developing new sensors and actuators for human use and interaction
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
An Investigation of the Applicability of Sugar and Wax Valves for rapid molecular diagnostics
Full text linkPaper-based Loop-mediated Isothermal Amplification (LAMP) of nucleic acids is a low-cost molecular diagnostic method to detect biological pathogens and has been successfully combined with lateral flow devices. This invention is a low-cost visual detection technique of various disease. However, existing assays require multiple user-activated steps and are relatively complicated to use at the point of care due to steps like the heating process. This project aimed to investigate an ideal valve for integrating LAMP onto the lateral flow assay. An ideal valve needs to be able to stop the fluid flow for 20-60 minutes under 65 degree to complete the amplification and release the water flow automatically. Sugar and wax were examined as potential valve materials. The sugar valve was tested by pipetting various concentrations of sucrose solution onto paper strips and drying the strips. For these valves, the time it took for water to dissolve the sugar was the total valve timing. The wax valve was made by dipping the paper strips into melted wax and then cooling. The melting point of the wax was higher than 65 degree so that after the heating process, the wax valve could be “opened” by increasing the temperature and allowing the fluid to flow. The sugar valves lacked repeatability due to environmental conditions such as humidity and difficulty of distributing the sugar solution evenly on the paper strips. In contrast, the wax valve was demonstrated to have incredible reliability and control over fluid flow. We managed to stop the water flow completely with wax valve and open it within 2 minutes. This paper proved that wax has potential to be a good valve for paper-based loop-mediated isothermal amplification
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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